钴负载凹凸棒石基复合吸附脱硫剂脱除SO2的实验研究

以甘肃产凹凸棒石(ATTP)为基体,辅以活性氧化铝、成型刺等成分,经造粒后附载过渡金属氧化物Co3O4,制得了一种新型复合吸附脱硫剂Co3O4-AlO3/ATTP.通过对该物质的动态脱硫实验,研究发现ATTP含量、焙烧温度、脱硫剂含水率及过渡金属浸渍液浓度对SO2脱除性能均有影响,当ATTP含量为60%～70%,焙烧温度为600℃,Co(N03)z浸渍液浓度为20%左右,且脱硫荆的含水率达到15%～30%时,该复合吸附脱硫剂具有较强的吸附性能和催化脱硫能力,其硫客可高达19.74%,脱硫效果优于CuO-γ-Al2O3/ATTP脱硫剂和CuO/γ-Al2O3脱硫荆.     

钻井液流变模型的优选

选择合适的工程浆液流变模型是现场生产中很重要的技术问题。基于最小二乘法原理利用Visual C＋＋高级语言编制程序对试验数据进行拟合,可求得实测浆液的常用流变参数值,绘制各常用流变模式与实际流型的曲线,从而优选出最合适的流变模式。     

Upper Cambrian carbonate sequences of the Argentine Precordillera and the Steptoean C-Isotope positive excursion (SPICE)

Carbon and Sr-isotope profiles in Upper Cambrian platformal carbonate Formations in the Precordillera, western Argentina (Zonda, La Flecha and La Silla Formations), were constructed for three representative sections: (a) Quebrada de la Flecha, Eastern Precordillera, (b) Cerro La Silla, Central Precordillera and (c) Quebrada de La Angostura, northern part of the Central Precordillera.

At Quebrada de La Angostura, upper part of the La Flecha Formation, δ¹³C_carb varies continuously up-section from − 2.0 to + 5.6‰ (PDB) and records the SPICE anomaly (+ 5‰) reported for the first time in South America. The peak of this excursion is characterized by intercalated 2 m thick beds of black shale with marl and limestone that record the onset of a sea-level change.

The Steptoean Zonda Formation dolomites at the Quebrada de la Flecha exhibit a total δ¹³C range from − 2.7 to + 0.6‰ with discrete positive anomaly about 200 m from the transition to the overlying Sunwaptan La Flecha Formation. Pronounced C-isotope anomaly (− 5.6‰) is observed in the La Flecha Formation at about 300 m below the transition to the La Silla Formation.

At the Cerro La Silla section, the Zonda Formation exhibit δ¹³C values of  − 1‰, increasing slightly at the transition to the La Flecha Formation (− 1 to 0‰). The transition of the La Flecha to the La Silla Formations is characterized by alternation of black shales and dolomitic limestone with a discrete positive C-isotope excursion, probably corresponding to the SPICE.

At the Quebrada de La Flecha, ⁸⁷Sr/⁸⁶Sr for the Zonda Formation varies from 0.70924 to 0.70955 and for the La Flecha Formation from 0.70908 to 0.70942. At Cerro La Silla this ratio varies from 0.70914 to 0.70923 for the La Flecha Formation, and from 0.70898 to 0.70980 for the La Silla Formation. At the Quebrada de La Angostura, ratios for the La Flecha carbonates range from 0.70918 to 0.70993. The overall variation of ⁸⁷Sr/⁸⁶Sr is consistent with globally reported Upper Cambrian seawater values at ca. 500 Ma.

The unambiguous record of SPICE in the La Flecha Formation at the Quebrada de La Angostura supports a Steptoean age for its deposition and allows precise local, regional, and global stratigraphic correlation. The pronounced negative C-isotope excursion recorded in the La Flecha Formation carbonates at the Quebrada de La Flecha is likely equivalent to that registered in Sunwaptan carbonates of North America and Australia, and might be tied to a global event, as a valuable tool in stratigraphic correlation (SNICE, acronym for Sunwaptan negative isotope carbon excursion).     

A preventative approach to mitigating CW interference in GPS receivers

In the global positioning system (GPS), code division multiple access (CDMA) signals are used. Because of the known spectral characteristics of the CDMA signal, continuous wave (CW) interference has a predictable effect on the different pseudo random noise (PRN) spreading codes (unique to each satellite) depending on the Doppler frequency of the signal. The Doppler frequency for each signal is also predictable once the receiver position is known. As different satellite signals have different Doppler frequencies, the effect on the signal quality is also different. In this paper first the effect is studied analytically. The concept of an “exclusion zone” is defined and analyzed for each satellite. This exclusion zone, where that satellite should not be used due to interference degradation, is shown to be predictable for each satellite as a function of time. Using this prediction, the CW interference effect on the positioning quality of the receiver can be mitigated by ignoring the affected satellites within exclusion zones when performing position evaluation. The threshold beyond which a satellite should be excluded is then derived by studying the mutual effects of the geometry and the signal quality of that satellite on the positioning quality. Receiver autonomous integrity monitoring (RAIM) uses redundancy in measurements to perform an internal consistency check to see if all of the measurements are satisfactory. In this paper this technique is also used to mitigate the effect of CW interference on the positioning accuracy. Finally it is shown that the prediction of the exclusion zone for each satellite outperforms the RAIM algorithm in mitigation the effect of the interference when 5 satellites are visible. An erratum to this article can be found at     

响应面法优化鹿角菜中岩藻多糖的提取工艺

在单因素试验的基础上,利用Box-Benhnken中心组合实验设计,采用响应面法对鹿角菜(Pelvetia siliquosa)中岩藻多糖的提取工艺进行优化。结果表明,液料比、水浴温度和水浴时间对岩藻多糖提取率均有显著影响;最佳提取工艺条件为:液料比(m L/g)32、水浴温度90℃、水浴时间8.4 h,此时岩藻多糖最高提取率为5.2005%,与理论值5.2153%相比,相对误差很小。响应面模型与实际情况拟合良好,采用响应面法对鹿角菜中岩藻多糖提取条件进行优化合理可行。     

Multiphase dolomitization of deeply buried Cambrian petroleum reservoirs,Tarim Basin,north‐west China

Cambrian dolostone reservoirs in the Tarim Basin, China, have significant potential for future discoveries of petroleum, although exploration and production planning is hampered by limited understanding of the occurrence and distribution of dolomite in such ancient rocks buried to nearly 8 km. The study herein accessed new drill core samples which provide an opportunity to understand the dolomitization process in deep basins and its impact on Cambrian carbonate reservoirs. This study documents the origin of the dolostone reservoirs using a combination of petrology, fluid‐inclusion microthermometry, and stable and radiogenic‐isotopes of outcrop and core samples. An initial microbial dolomitization event occurred in restricted lagoon environments and is characterized by depleted δ¹³C values. Dolomicrite from lagoonal and sabkha facies, some fabric‐retentive dolomite and fabric‐obliterative dolomite in the peloidal shoal and reef facies show the highest δ¹⁸O values. These dolomites represent relatively early reflux dolomitization. The local occurrence of K‐feldspar in dolomicrite indicates that some radiogenic strontium was contributed via terrigenous input. Most fabric‐retentive dolomite may have precipitated from seawater at slightly elevated temperatures, suggested by petrological and isotopic data. Most fabric‐obliterative dolomite, and medium to coarse dolomite cement, formed between 90°C and 130°C from marine evaporitic brine. Saddle dolomite formed by hydrothermal dolomitization at temperatures up to 170°C, and involved the mixing of connate brines with Sr‐ enriched hydrothermal fluids. Intercrystalline, moldic, and breccia porosities are due to the early stages of dolomitization. Macroscopic, intergranular, vuggy, fracture and dissolution porosity are due to burial‐related dissolution and regional hydrothermal events. This work has shown that old (for example, Cambrian or even Precambrian) sucrosic dolomite with associated anhydrite, buried to as much as 8000 m, can still have a high potential for hosting substantial hydrocarbon resources and should be globally targeted for future exploration.     

Utilization of high-resolution EGM2008 gravity data for geological exploration over the Singhbhum-Orissa Craton,India

High-resolution EIGEN6C4 and EGM2008 Bouguer gravity data of 2190 degree spherical harmonic over the Singhbhum-Orissa Craton, India, have been generated from the International Centre for Global Earth Models. The Bouguer gravity anomaly difference maps of (i) in situ and EIGEN6C4, (ii) in situ and EGM2008 and iii) EIGEN6C4 and EGM2008 of the study area are compared. It reveals that EIGEN6C4 has lesser systematic error than EGM2008. However, from different profile plots of Bouguer gravity, east–west horizontal derivative and north–south horizontal derivative anomalies of the in situ, EIGEN6C4 and EGM2008, it is observed that most of the signatures of lithounits and geological structural elements are delineated very well by EGM2008 and match 94–98% with those of EIGEN6C4. Further, the Bouguer gravity, east–west horizontal derivative and north–south horizontal derivative anomalies of EGM2008 data over the study area have been used effectively for identifying various lithounits and geological structural elements.     

Anomalous drip in the Punkva caves (Moravian Karst): relevant implications for paleoclimatic proxies

The anomalous drip in the Punkva caves (Moravian Karst) shows specific hydrogeochemical properties such as low SI_calcite ~ 0.14 ± 0.11 (standard deviation), low mineralization (4.53 ± 0.42) × 10^?3 mol l^?1, and enhanced values of δ¹³C (?7.85 to ?8.35‰ VPDB), Mg/Ca × 1000 ratio (45.7 ± 3.3), and Sr/Ca × 1000 ratio (0.65 ± 0.06). By these properties, the anomalous drip significantly differs from other regular drips in the same cave and other caves in the region. The study suggests that the anomalous drip properties are a consequence of prior calcite precipitation or/and water mixing along the water flow path. As the former processes are spatially controlled, the knowledge of dripwater flow path seems to be necessary for correct paleoclimatic/paleoenvironmental reconstructions. Copyright © 2015 John Wiley & Sons, Ltd.     

长江三峡非正常含炭粘土沉积及其地质灾害意义

在长江三峡工程库区巫山、奉节、云阳等新县城进行工程地质勘察过程中, 发现在长江岸坡地带存在含炭粘土沉积.对部分含炭粘土进行了14C年龄测定, 年龄测定结果与该含炭粘土层所在高程相当的阶地形成年代不一致, 含炭粘土为非正常沉积.非正常含炭粘土的存在与发现, 一方面揭示出巫山等移民新县城斜坡经历了非正常的形成演化; 另一方面说明长江三峡河谷演化过程中夹杂着突发的地质灾害事件.      

“死碳”对14C年代测定影响的初步研究

在回顾14 C测年技术发展的基础上,指出了影响14 C测年精度的各种因素,并初步讨论了“死碳”对14 C年代的影响。通过对岩溶区“死碳”的成因分析以及对碳酸盐样品的14 C年代学研究,认为酸的来源不同,是造成岩溶区样品14 C年代偏老的原因;局部环境中“死碳”释放是造成水生样品14 C表观年龄偏老的主要原因。由于影响岩溶区样品14 C年龄的因素是多方面的,目前尚无有效的校正办法。为此,作者在讨论了洞穴碳酸盐样品年代的可靠性及影响因素的基础上,提出了用交叉对比定年的方法解决“死碳”对14 C测年的影响问题和在岩溶地区谨慎使用14 C年龄的建议。